carjacking and high-speed chase in Colorado. A Denver area mom horrified as a man races off in her SUV with her 4-year-old son in the backseat. The video you're about to see is from our station in Denver, KMGH. You can hear the reaction from the anchors as they watch it unfold. ABC's Clayton Sandell has the story. He just passed moo he. Reporter: The race to stop this stolen SUV crisscrossing Denver kicks into overdrive when police realize the suspect has a passenger. We do believe that the 4-year-old is still in the vehicle. Reporter: 4-year-old Allen was in his mom's car. She ran inside for coffee leaving the engine running. "When I came back out the car wasn't there anymore." She says. Little Allen still in the backseat as the suspect, 28-year-old Ryan stone, makes his next move. All on live TV. Uh-oh. He's stopping. He'stoing. Looks like he's carjacking that person right there. Putting that person out of the -- Oh, my god. Reporter: Stone leaves the boy behind but speeds on sometimes going the wrong way. He is now coming up to a busy area right here. Reporter: Here he clips and seriously injures a state trooper who was trying to puncture the car's tires. The trooper was lucky. He's expected to fully recover. He just ran into somebody. You saw him right there. In danger unknowingly. Oh. Uh-oh. Oh. Let him go. Okay. Oh, my goodness. Oh. That -- Third automobile today. One hour and half a dozen crashes later -- Oh. Oh! Oh, my goodness. We just saw that collision. Reporter: -- Stone finally gives up. Allen with his teddy bear and now reunited with family is okay. What happened in the car? We flew. Reporter: "We flew," he says. Police say they're letting mom off the hook. The family's high-speed trauma punishment enough. For "Good morning America," Clayton Sandell, ABC news, Denver.

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